Does anyone know if US Anodizing, or anywhere else, can do Type III anodizing in flat dark earth?
I might be making some modifications to my new SBR lower receiver and if I do, I’ll most likely want to refinish it properly. Since I’ve already decked it out in assorted other FDE parts, I was thinking that I’d do the upper, lower, charging handle, and reciever extension in FDE while I was at it and make it all match.
Any anodizing experts in the house?
Im not an “Anodizing expert” but, I just had some parts type III hard coat anodized (7075 T6) without dye. When I got them back they were kind of a greyish color. A little wipe with some oil and they turned gold/tan. 
Who knew, very cool though. I was told the only color they can dye with type III hard coat is either no dye (flat light grey) or black.
Thats my experience. 
The hole in your receiver will be out of spec if you strip and reanodize an already anodized receiver.
True,
You can specify your thickness of anodizing (I did anyway) and depending on your spec, the build on the surface can render things hard to work with.
How I understand it, anodizing isnt a coating. Its basically an etching (corrosion) of the surface of the aluminum, with 50% penetration and a 50% build on the surface. IE; If you specify a .002" (or 2 mil) thickness, then you’ll see a .001" (or 1 mil) build on the surface. If its a hole or a cylindrical part, you’ll see the build twice. Making the hole .002" smaller or the cylindrical part .002" larger in diameter.
Hope that helps…
You cannot get back to the original dimensions after it has been stripped once as some base material will be removed when stripped.
Be that as it may, US Anodizing has refinished quite a few M16 lower receivers and managed to keep the pin holes in spec. In other words, these things can be managed by a competent anodizer.
That isn’t what I’m asking.
All I want to know is if the various parts I’ve seen anodized in FDE were done in Type II or Type III and if the latter, who can do the job.
you guys worry too much I had my reciever media blasted with alum oxide and coated with gun kote. everything is still up to spec.
I think I saw it posted on here in another thread that the FDE anodizing that my spikes tactical upper/lower has on it is milspec type III hardcoat.
Maybe try a search for spikes tactical and scan a few threads to see if you can find the comment from the user “spikes rep” or something like that.
EDIT: Here you go, scroll down in this thread: https://www.m4carbine.net/showthread.php?t=28631
what about the surefire weapon lights. they’re type3 hard anodized but they look goldish tan?
I disagree.
You cannot get back to the original spec no matter who you are.
This is not a knock against US Anodizing as his finish is very nice and he is good if you want to do a custom bare receiver that has never had finish before.
Every receiver that I ever seen has opened up holes after being reanodized. I can tell instantly when picking up a gun that a receiver has been reanodized just by the way it feels.
Every hole that I have seen will get opened by atleast .002" in diameter which is +.002 out of spec from USGI.
So what, that’s not what he’s asking.
He is spreading misinformation.
Really? Where are you getting your information?
According to the TDP the trigger/hammer pin holes should be 0.156 +/- 0.0015. Maintaining a manufacturing tolerance of 0.0005 (that’s 5 ten-thousandths of an inch) is pretty damn good. If you take that manufacturing tolerance and stack it either way on the allowed tolerance you’re at either 0.002 or 0.001.
If you can consistently feel and call a 0.001 difference in the alignment and movement of the trigger/hammer pins, you’re my new hero.
So US Anodizing hasn’t managed to successfully refinish lowers? I’ve had 16 parts for a machine I build at work that have precision locating holes, stripped and refinished without changing the dimensions of the holes. Though we didn’t use US Ano, I’m of the opinion that it should possible. But admittedly, I’m no anodizing expert as you undoubtedly are. Any other anodizing experts out there, that can corroborate this?
Most people say that TRUE FDE cannot be anodized very easily (if at all), and to my knowledge, FN is the only company that has got it anywhere close, with the exception of Surefires new “Desert Brown” Scout light. I’ve only seen pics of the Scout light however, but from the PICS I’ve seen online, it looks more like FN’s SCAR ano jobs. However, as we all know, these FDE ano jobs can REALLY look different in pictures taken in various lighting.
Daniel Defense has done what they call a “FDE” ano job on their RIS rails, and it’s SO FAR from FDE it shouldn’t even be called FDE. It’s a bronze basically.
I have pics of my SCAR that look gold/brown/FDE and everything in between.
I guess it all depends what you want and like.
I cannot personally tell you who does “FDE-ish” ano jobs, but I’m sure someone out there will do it.
On a similar note, I met a guy the other day in a local gun shop, who came down from C3 Sports in Atlanta, GA, and he had a bunch of lowers that were ano’d in various colors that he was trying to sell.
He whipped out what he called a “FDE” one, and it looked SILVER/GREY I swear. I couldn’t believe it, and thought that either he was crazy, or I was seeing things…
It’s perfectly possible. It depends on the thickness of the anodizing, how much is stripped off and what the original dimensions of the hole are. Even if it doesn’t get back to the original dimension you should still be able to get it back to within the specified range. Please don’t take this to mean that it can always be done, just that it’s possible. That said, I’d probably just Cerakote/Gunkote it instead.
I agree.
Exactly what I was getting at when I said “specify your thickness”.
I also said “Im not an anodizing expert”.
If just the build on the surface is removed, it seems to me you could get back to where you need to be. That might not be deep enough to take away all the dye though.
That is before anodizing. After anodizing the hole is suppose to be 0.154" because anodizing grows 0.002" diameter in the hole.
When you strip and reanodize, the hole will be at minimum 0.156" This is out of spec as the USGI blueprint has a clearance for anodizing.
You can only specify thickness to a certain extent which will not make up for a loose hole. You cannot just keep growing the thickness to however thick you want it.
Victor re-anodized my Colt M16A1 lower a few years ago and everything fits exactly the way it did prior to my sending it his way. It runs like a scalded dog too.
Go with Victor, he really knows his way around anodizing the AR15/M16 series.